1. Field of the Invention
The present invention relates to a vehicle bumper structure that detects a collision with an object such as a pedestrian or the like.
2. Description of the Related Art
Japanese Patent Application Publication No. 2000-225907 (JP-A-2000-225907) describes an arrangement in which a load sensor is provided for detecting a frontal collision of a vehicle with an object, e.g., a pedestrian. Specifically, a groove extending in the vehicle width direction is formed in the front surface of a front-bumper reinforcement, and an elongated load sensor is received in the groove flush with the front surface. In the back surface of a front-bumper absorber, a pair of upper and lower grooves extending in the vehicle width direction is formed. A protruding portion (or a push portion) provided between the upper and the lower groove is disposed to correspond to the load sensor.
The structure described in JP-A-2000-225907, however, leaves a room for improvement in the following respects. In particular, if the height of the load sensor is reduced and the front-bumper absorber is configured to have a low height in consideration of the kind of a vehicle or in terms of vehicle weight reduction, the front-bumper absorber may topple down toward the front surface of the front-bumper reinforcement (toward a side opposite to the load sensor in the vehicle height direction) depending on an impact direction, which causes a possibility that the impact load is not sufficiently transferred to the load sensor.
In an effort to prevent the front-bumper absorber from toppling down, the front-bumper absorber may be further extended up to a portion where there is no load sensor. In this case, however, the impact load is partly transferred to the front-bumper reinforcement through the extension portion, so that the impact load input to the load sensor is reduced in proportion thereto. This solution is therefore undesirable.